a) convergentIn evolutionary biology, convergent evolution is the process whereby organisms not closely related (not monophyletic), independently evolve similar traits as a result of having to adapt to similar environments or ecological niches. An example of convergent evolution is the similar nature of the flight/wings of insects, birds, pterosaurs, and bats. All four serve the same function and are similar in structure, but each evolved independently. Convergent evolution is similar to, but distinguishable from parallel evolution. Parallel evolution occurs when two independent species evolve together at the same time in the same ecospace and acquire similar characteristics (extinct browsing-horses and extinct paleotheres).